The mobile friendliness report in Google Search Console only shows a sample of all URLs. A decrease in the number of selected URLs does not indicate problems, according to Google.
Some webmasters may wonder why the mobile friendliness report in Google Search Console has a small number of URLs and why not all URLs are recorded there. Even for websites with thousands of URLs, the mobile friendliness report may only show a double-digit number of URLs.
However, there is nothing to worry about. When asked by Twitter, Johannes Müller explained that the report on mobile friendliness only shows a sample of all URLs – in contrast to the report on index coverage. If the report shows no errors, everything is ok:
Even if the number of URLs in the report on mobile friendliness is decreasing, this is nothing to worry about, according to Müller:
Müller admitted that there is certainly still potential here to make the report less confusing.